Each year tens of thousands of people are diagnosed with Repetitive Stress Injuries (RSI). RSI are a group of conditions caused by placing excessive stress or repetitive motion on a joint or a muscle. According to the Occupational Safety and Health Association (OSHA) RSI is leading work related health problem in the United States. RSI are reported to cost the government and businesses billions of dollars each year.
In the 1970's, the average age for someone to develop RSI was in the late 30's-early 40's. Now the average age for developing RSI is in the early-to-mid 20's.
Ergonomic disorders account for most of the RSI in the United States. Incorrect ergonomics and improper posture at computer workstations are contributing to increases in the number of reported health problems and repetitive stress injuries. It has been reported that 67% of adult computer users had experienced neck and upper limb pain in the previous month. Today, this number is greater due to the increase of computer use daily life.
The following are risk factors that lead to musculoskeletal pain that lead to computer related injuries (CRI): (a) awkward postures, (b) poorly designed workstations; (c) inadequate seating; (d) poor lighting; and (e) glare. FIG. 1 illustrates a rounded and dysfunctional spinal posture, commonly referred to as a “C-Spine” position 2 which is the partial result of the poorly designed workstation 4 and inadequate seating 6. In contrast, FIG. 2 illustrates an ergonomically correct posture, referred to as a “S-Spine” position. An ergonomically correct posture normally requires and includes (a) proper placement of the buttocks or posterior against the back of the seat pad; (b) a supported lumbar region; (c) sitting erect with the shoulders in line with the pelvis and slightly apart from the seat back; and (d) an erect neck posture, in line with the shoulders and pelvis. In addition, FIG. 2 also illustrates a number of the important adjustments and positioning necessary to achieve this ergonomically correct posture while sitting at a computer workstation. These important adjustments include: (a) having the screen at eye level 8; (b) having the screen at an arm's length distance 10 from the user; (c) a chair with lumbar support 12; (d) arms close to the body and elbows at 90 degrees 14; (e) keeping the wrists straight, with a wrist rest if necessary 16; (f) the buttocks or posterior placed at the back of the chair 18; (g) use of an adjustable chair for correct back support, height and forward pelvic tilt 20; (h) a knee angle greater than 90 degrees 22; and (1) feet flat, with a foot rest if necessary 24.
There is often a ten to fifteen year latency before RSI injuries start to develop. This means that it is important to encourage the development of correct posture habits as early as possible. Childhood back, neck and shoulder pain have been found to be a predictor of adult back, neck and shoulder pain. It is thus important to address the causes of discomfort at a young age in order to prevent musculoskeletal injuries in adulthood. On an increasing basis, children are using computers at younger and younger ages which make them more susceptible to poor posture and RSI when they are older. In 2003, it was found that 91% of children in the U.S. ages 3-18 used computers. Similar statistics are found in Canada, Australia, and other industrial countries. Approximately 80% of children first use a computer in kindergarten, and by the time they reach high school, approximately 97% regularly use computers. University students report that using a computer from young ages causes a habituation and cumulative effect that makes them more likely to have computer related injuries when they are older.
Studies of school age students show that children do experience musculoskeletal discomfort similar to that of adults during computer use and in fact, children are experiencing significant musculoskeletal discomfort associated with computer use.
In studies and surveys done on children, an average of 60% of students reported discomfort associated with computer use. Students are sitting in schools with poorly aligned posture and improper workstation ergonomics. In one study, for example, it was found that no student was found to have acceptable posture. Aside from actual furniture, other issues such as the location of computer screens and documents and the type of keyboards and other input devices that are most appropriate, have seldom been considered.
Ergonomic intervention and education have been shown to reduce discomfort caused by frequent computer use. In one study, when students started to use adjustable tables and chairs, the muscle tension level fell significantly, while the control group showed an increase of head ache, and muscle pain. Another study reported that students that received ergonomic and educational interventions showed a significant decrease in discomfort/pain, with 41% reporting discomfort/pain at the start of the study, down to 18% after year two and 8% after year three.
Accordingly, there is a need for an effective device and method that can be used to train users, including children and young adults, to maintain correct posture while seated at a computer workstation.